AWARDEE OF AGRONOMY PRIZE

YAN JI

Abstract

Professor Yan Ji (also known as Chi Yen), an agronomist, was born on May 24, 1924 in Chengdu, Sichuan Province. He graduated from Department of Agronomy, West China Union University in 1948. He became assistant instructer in Department of Biology, and promoted to decturer later. In 1953, he joined Sichuan Universitys Department of Agronomy in the College of Agriculture, which was separated from Sichuan University becoming Sichuan Agricultural College, and moved from Chengdu to Yaan in 1956. He was promoted to asscociate professor in 1963 and to professor in 1982.
Prof. Yen has been creating better wheat for about fifty years. He has also been doing research in plant morphology, cytogenetics, taxonomy and systematics in tribe Triticeae of the grrass family (Poaceae). He is the supervisor for several Ph.D dissertations and published more than 150 articles in national and international scientific journals. He was given the title of Excellent Workers by both provincial; and national governments, and awarded First Class National Invention Prize and prizes by provincial and national sciences conference as well as from Sichuan provincial government and Ministry of Agriculture.
The greatest achievement Prof. Yen has made in his career is in wheat improvement. He has increased wheat yield from 2250-3000 kg per hectare to 5〖KG-*6]520-6000 kg per hectare. Since 1960's, every big achievement in wheat improvement in Sichuan has the contribution from Prof. Yen. The wheat cultivars bred by Prof. Yen and his colleagues, such as Yaan Zhao (Ya-an Earliness), Da tou huang (Big Yellow Head) and Zhu Ye Qing (Green Bamboo Leaf), were once grown in half of the farmland (more than a million hectares) in Sichuan Province. Prof. Yen designed, on the basis of his theory of uneven organ develoment in higher plant, an wheat ideotype that would have a short first mprphogenesia stage and extended second and third morphogenesis stages. This new high yielding wheat should have few tiller, large spikes and short growth period. With multiple crossing and shortened nursery, genes from a wide range of resources converged together, and, in this way, Prof, Yen was able to create such new wheat cultivers. For example, Fan 6, one of these new wheat cultiovars, yielded 5250-6000 kg Per hectare with highest up to more than 7500 kg setting a new record in Sichuan. These cultivers were resistant to 13 physiological strains and 20 physiological forms of strip rust, controlling strip rust in Sichuan for more than 20 years. For further increase quality and yielding of wheat in Sichuan, Prof. Yen is studying and introgressing genetic resources from wheat relative species and genera. For instance, he has identied drought tolerance from a wide species that is growing in the Gobi desert of Xinjiang and wet tolerance from a species from Japan. He transferred into wheat the resistance to preharvest sprouting from wheats relative species Aegilops tauschii. He also introgressed multispikelet genes from rye and produced wheat with more than 30 spikelets.
In the basic researchs, Prof. Yen studied the mophogenesis of supernumerary spikelet of wheat and hooded awn of barley, and proposed the theory of multiple secondary axes, which brilliantly expounds the organ and development of organs in higher plant. He also discovered the conjugation tube and opening among meiotic cells of higher plant. These observations increased our understanding of the mechanism of spontaneous chromosome doubling and the origin of high level polyploids and aneuploids.